Computer systems and office machine systems are commonly linked together in a network that may be wired or wirelessly implemented so that multiple users can all access the facilities of various office machines such as printers, faxes, copiers, scanners, and the like from their desktop or laptop computers. Typically, using the printer as an example, multiple users will wish to send printing tasks to the commonly-shared printer for printing. Modern high-speed office and production printers have been developed that can easily handle the throughput required to support a large number of users virtually simultaneously. Such machines require detailed expert service to maintain peak operational capacity. During service times, either the service technician must manually disable the inputs to the machine from users, such as by disconnecting the interface cables, or must entirely remove the machine from service in the system. This is referred to as “going offline”. Operations for diagnostic purposes often require the technician to move about the machine and to enter control commands from various physical locations while tests are being performed This can be cumbersome and time-consuming and inconvenient as well, especially on large-sized, high-speed printer systems.
One such high-speed printer system, for example, is the Model 4100 printer, available from International Business Machines Corporation, Armonk, N.Y. Such a printer is capable of printing in duplex, that is, on both sides of paper, for production printing at rates up to 1220 impressions per minute, where impressions are defined as being one 8.5″×11″ content printed on a sheet of paper. Such machines are typically approximately twenty to forty feet long, or longer depending on what paper feeding, collecting, collating or other apparatus may be provided with them. This means that service operations require a good deal of physical movement about the machine on the part of the service technician to inspect operation, make adjustments, enter test commands or to observe indicators. Typically, such printers receive input printing tasks from a mainframe computer or printer server and from directly-attached networks of devices such as user's computers which may be connected using ESCON® (Trademark of IBM Corporation, Armonk, N.Y.) an optical channel attachment used with IBM mainframe computers, Ethernet, Ficon, an optical fiber channel connection, or other high-speed channel links. In such a system, incoming commands can be generated from a multitude of users, all of which would interfere with a service technician's tasks of diagnosing and correcting problems and the like. In fact, with the widespread use of wireless systems based on radio frequency, infra-red, optical or other types of communication network capabilities, it is almost inevitable that interference with the technician's task will result unless some means is provided that will enable the service person to control all the operations of the printer while simultaneously preventing any input commands from would-be users from reaching the printer.
What is desired is a special lockout apparatus and method that blocks incoming commands from the computer system, the print server or users while enabling control commands to be acted upon if they are from the service technician. Control over the operation of the device can be effectively transferred from the internal controller of the device to the service technician, who may carry a wireless hand-held computer, so long as the lockout apparatus and method are in use The “primary” control device then becomes the technician's handheld computer device and commands from the mainframe or server are ignored until service is ended and control is transferred back to the device's own controller.